The CamelBak ThermoBak is a tough, cost-effective, versatile pack that has been battle-tested by troops around the globe. The ThermoBak features the very tough and combat proven Antidote Reservoir. The reservoir was designed for allowing 100oz/3.0 liters of water supply and providing maximum adaptibility for all environments. Beat the heat and take water anywhere you go with the CamelBak ThermoBak Hydration Pack.